Honda Fit - Auto (non-hybrid) what I've learned

dpadams · #1 06-14-2008, 07:50 AM

First: This website has really helped me improve my mileage and I appreciate what you all have taught me. From your recommendation, I also got a Scangauge II. Expensive, but worth it for me.

Safety is my highest concern - followed by at least a modicum of good manners - then by best Gallons per week. I don't have a hybrid because I'm very tall and don't fit into them safely (my head will hit the roof in an accident).

I have the Honda Fit with auto tranny. You might think the manual transmission would be a better choice, but I get into a lot of traffic jams and don't like manual for that. Also, the AT has taller gearing. So I get 60mph at about 2100 rpm - however, I'd love to have the control of a MT. Maybe the Fit Sport with paddle shifters would be better - just don't know.

I'm just a newbie, so I'm no expert here. But I'm grateful to your posts, and thought I would try to give back a little by sharing my thoughts. So here is a fairly long summary of my experience in trying to reduce my "gas used". My commute is fairly long (26mi) and accounts for the majority of my miles. Only about 3 miles on local roads and the rest are "highways". Keep in mind that during commuting hours in the Boston area "highways" become slow at times. During the weekends, my travel is on local roads and urban trips so the mpg drops. I've been averaging about 44mpg per week with 49mpg commuting and 39mpg at home.

One thing that interests me is the physics/engineering that affects mpg. Here are my working premises:
1. Don't waste gas (coast to lights, light timing, follow at a decent distance dwb etc).
2. If you don't need the engine - coast (I don't FAS because, for me, it is a safety issue and I don't have a hybrid which will do this safely).
3. If you do need the engine - use it at its maximum efficiency.

I learned all of these by reading posts on this website and thinking about how I can implement these ideas on a non-hybrid AT.

On my Scangauge II, I display Engine Load (LOD), MPG instantaneous, MPG average for the current trip, and Gallons used for the current Tank. I have found that for my car the best efficiency seems to be at an engine load of between 90 and 94 percent at about 2000 rpm. How did I find this? Well, I looked up the torque curve for my engine and found the first peak was at about 2000 rpm. So that gave me a clue. Also, I read posts on this website which confirmed this idea. Then I watched the instantaneous MPG vs LOD while accelerating. As I increase the LOD, there comes a point when the MPG stops dropping quickly. For example at LOD = 70 the MPG might be 33 at 2000rpm. Then I'd push harder on the gas - increasing the LOD to 88. The MPG drops to 30, but I can feel (watch the speedo) more acceleration, so I'm spending less time at this acceleration. If I increase the LOD to 94, the MPG drops only to 29mpg etc. But if I push it further to LOD=99, I don't feel much more acceleration and the mpg drops to about 25mpg.

The Honda does a pretty nice job of selecting a gear that provides good FE, so I've stopped worrying too much about what gear I'm in. I just watch the LOD, try to keep the AT in its highest gear.

One thing I've found interesting. I've started a car pool to work. When I did this, I noticed a significant drop in my FE. This is because my home/weekend MPG is not as good as my commuting MPG. However, my gallons per week obviously improves. That is why my main goal has shifted from MPG to GPW ( actually what I measure is weeks/tank). I've gone from 1 week/tank to 2 weeks/tank by carpooling.

That's about it. And thanks to all of you (especially Wayne) for your help and encouragement.

MikeN · #2 06-14-2008, 08:45 AM

Congrats on your efforts.... nice post as well.

99HXCivic · #3 06-14-2008, 01:33 PM

No, a Scanguage is not expensive. A Dashdyno is at $379!

xmr · #4 06-14-2008, 03:27 PM

dpadams:
How hard is it to get in and out of your Fit? My wife has arthritis and for the last 9 years we have been restricted to pickups and vans for easy egress. the roof height for the fit is listed at 60 inches which is better than most small cars. (civic is 56.3)

dpadams · #5 06-14-2008, 04:45 PM

xmr,

I'm not sure about arthritis. I find the car easy to get in and out because it is tall and has a pretty high seat. Keeping in mind that I have the seat all of the way back. If your wife is shorter, she might find it different with the seat forward (it is on a ramp that increases height as you move forward). For something like this, I'd just try one out.

For my experience, I did not fit well into the following cars:
Camry, Accord, CRV, Civic, Civic hybrid, Prius, Subaru Outback. I found the Toyota's worse than the Honda's generally.

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A few more notes to my original post. I realize that many in this group measure MPG carefully. When I posted my mileage - this was my recollection. I do measure tank-to-tank and compare it with the SG. However, I don't write it down. I was just putting in numbers that I think I've been getting.

Also, I did notice last winter that my MPG dropped by about 10%. The numbers I gave were for warm and dry weather.

A bit more about P&G. On 55mph roads I pulse to about 60mph. On 65mph roads I pulse to about 65. My glide depends on traffic. If someone is pushing from behind, I'll glide by about 5mph - if not, I'll glide by 10mph.

I ride in the right lane and take advantage of mergers to lengthen the glide. Sometimes I have to ride in the 2nd lane because there is someone poking along there. People drive over a pretty wide range of speeds on the highways I use, so I have to adjust accordingly.

shiroboi · #6 06-16-2008, 04:26 PM

I don't know why I like the Fit so much but I'd highly consider a manual fit sport as my next car. My only gripe is that it dosen't have a dead pedal for your left foot but I heard you can get an aftermarket one.

PaleMelanesian · #7 06-16-2008, 04:58 PM

I think you'll get better results by stretching your glides even farther. 5mph is barely worth the effort. 10mph is a good start. 15+ mph is good.

koreberg · #8 06-16-2008, 08:01 PM

@shiroboi

no dead pedal!! that is a deal breaker.

shiroboi · #9 06-16-2008, 08:16 PM

Well, like I said, theres after market solutions for the lack of dead pedal. Its not that much of a deal breaker in my book.

kayasbluetaco · #10 06-16-2008, 08:48 PM

Quote:

Originally Posted by PaleMelanesian

I think you'll get better results by stretching your glides even farther. 5mph is barely worth the effort. 10mph is a good start. 15+ mph is good.

Wow.... that would be a tough one around here. Too much traffic. I am lucky if I can let it go down about 8 MPH at a time without a tractor trailer up my tailpipe... I had one within about 1 foot from my bumper today, and I was doing 60. I was afraid to glide, (his grill filled up my entire rearvire mirror!) so I had to dwl until he got the hint I wasn't going to speed. It was a construction zone (50 mph) as it was, and he had plenty of room to go around me. Bummed me out too, because I was on a good roll for the day and he screwed me up. But even those small 5 mph differences do help. Not the best, but still makes a difference.